1. Field of the Invention
The invention relates to recreational vehicle slidable rooms and more particularly to a slidable room driven by a scissors actuated sliding support mechanism capable to collapse and retract a sliding room support frame.
2. Description of the Prior Art
Recreational vehicles (RVs) offer users the opportunity to escape the rigors of everyday life and explore the world we live in. Resembling a small home on wheels, an RV is capable of transporting and comfortably sheltering a family for extended periods of time. The primary benefit of such a vehicle is to enhance the camping or traveling experience by providing the comforts of home away from home. Additionally, the occupant is given the option of braving the elements, commonly known as "roughing it", or retreating to the protection afforded by the RV. Thus the spirit of "roughing it" may be maintained without deprivation of the full camping experience.
Although freely mobile, as the size of RV's increase, the ease of handling tends to decrease. Responding to the need for more living space inside a smaller vehicle, numerous different RVs have been proposed with pop-up tops and slide-out rooms for selectively expanding the living area. Designed to be used only when the RV is parked, the assemblies generally slidably expand or retract from the side, rear or roof of the vehicle to form an extra access area, or room therewithin.
Variations on the idea of "popping" out a compartment to provide extra space within a vehicle have been disclosed. These compartments are often characterized by collapsible side walls terminating in an end wall with a mechanism to push out or pull in the walls. Such assemblies usually offer extra space only and are often not provided with a lower structural support framework to provide a true living space. One such variation on this general scheme was disclosed by the 1924 U.S. Pat. No. 1,513,227 to Cornelius et al, wherein a hand operated scissors network was used to manually extend and contract an accordion-like walled compartment. Although beneficial for use in automobiles of that era, such devices are not practical for recreational vehicle use since they do not provide support and driving force for practical use in deploying an RV room to be occupied by the vehicle occupants. Other variations in "popping top" schemes are illustrated in U.S. Pat. Nos. 2,561,921 to Guillot and 3,582,130 to Borskey.
In recognition of the need for a practical slide-out room, several different devices have been proposed. Included among those proposed are expandable camper bodies and enclosures (U.S. Pat. Nos. 4,133,571 to Fillios and 5,248,180 to Hussaini), and a slidable room assembly for RVs (U.S. Pat. No. 5,237,782 to Cooper). Envisioned for recreational vehicle use, these slide-out devices generally include accordion-like side walls laterally joined to a rigid end wall. Supporting the walls is a slidable frame carried from the main RV frame to slidably extend and retract from and within the main RV frame. A manually operated or motorized driving mechanism interconnects between the sliding frame and the main frame for expansion and retraction of the slide-out.
The trend in the RV industry over the last several years with regards to slide-out rooms has been to incorporate the entire slide-out assembly within the RV parent main frame. This development, as illustrated by the Cooper patent, has led to more feature inclusive mechanisms since any environmental effects from outside the parent frame during non-use are avoided. However, drive mechanisms associated with these assemblies have often correspondingly become more complex with the costs of repair and replacement correspondingly more substantial. This is due to the fact that access to the drive mechanism for the purpose of repair is often severely restricted thus adding to the time required for repair and maintenance thereby driving up the cost of repair.
Prior art driving mechanisms for RV slide-out rooms function in many different forms and generally share many of the same functional and structural characteristics. One such form uses toothed geared drive assemblies having racks or pivoted members which expand or contract upon rotation of a toothed gear. Devices of this type are disclosed in the Fillios and Hussaini patents. Other variations of slide-out drive mechanisms involve the use of threaded drive screws to drive racks and pivoted cross members as shown in U.S. Pat. No. 5,054,578 to Smillie, III et al. and the '782 Cooper patent.
Further efforts to provide a practical drive for slide-out rooms have led to the proposal of hydraulic cylinders. Resembling horizontally installed hydraulic jacks, these mechanisms slidably force the room open as the hydraulic room is extended and slidably close the room as the room contracts. Although straightforward in design, hydraulic systems often tend to be fragile in nature and, being subject to deleterious rigors of vibration in the transport of the RV over the roadway, can experience a relatively short service life. Additionally, activation of such systems is often from outside of the vehicle, thus exposing the operator to potentially adverse environmental conditions.
Alluded to above, a characteristic often shared by prior art drive mechanism designs is the intended location of the operating mechanism. Slide-out driving mechanisms are often installed as original equipment during manufacture of the RV. Termed "OEM" equipment, the installation locations of these devices are often chosen without consideration of the fact that it may be desirable to subsequently gain access to such mechanisms for repair and/or replacement. As a result, the devices are often incorporated within the confines of the RV main frame making repairs costly and replacement nearly impossible.
From the foregoing discussion, it is apparent to those skilled in the art that the need exists for a straightforward, low cost, reliable, and modular slide-out recreational vehicle room capable of OEM and aftermarket installation and replacement.